Temperature control of a workpiece placed on a mounting table is indispensable for controlling an etching rate, for example. Temperature control affects the uniformity of a plasma process performed on the workpiece and is therefore an important aspect of the plasma process.
An electrostatic chuck (ESC) that electrostatically attracts the workpiece by applying a voltage to a chuck electrode is arranged on the mounting table. In recent years, heater embedded electrostatic chuck mechanisms have been proposed that have heaters embedded within the electrostatic chuck such that the surface temperature of the electrostatic chuck may be rapidly changed through heat generation by the heaters. For example, Patent Document 1 discloses a temperature control technique implemented by a heater embedded electrostatic chuck mechanism. According to Patent Document 1, heaters arranged in the heater embedded electrostatic chuck mechanism are divided into two zones including a circular center zone and an edge zone that is concentrically arranged around the outer periphery of the center zone, and temperature control is implemented with respect to each of these zones.